In the execu​tive summary, sleep deprivation is described as involving "keeping detainees awake for up to 180 hours, usually standing or in stress positions, at times with their hands shackled above their heads."

One hundred and eighty hours is the equivalent of seven and a half days, and the summary also notes that sleep deprivation was "frequently concurrent" with slaps, forced nudity, and slamming detainees against walls—or "wallings," to use the CIA term.

Abu Hudhaifa, one detainee mentioned in the report, was subjected to ice water baths and 66 hours of standing sleep deprivation, before "being released because the CIA discovered he was likely not the person he was believed to be," according to the summary.

I reached out to University of Texas professor David M. Schnyer, a psychologist who has published on the impacts of sleep deprivation, to find out what happens to someone who has been forced to go without sleep.

Schnyer told me that "someone sleep deprived that long is usually psychotic with hallucinations and disruptions in basic cognitive functions."

After being up all night, subjects in the study were more sensitive to light and color, they had attention deficits, perceptual distortions in time and smell and even visual alterations. According to the study's press release, "many of those who spent the night even had the impression of being able to read thoughts or notice altered body perception," again, after only 24 hours of being awake.

Given that they were held awake as many as 6.5 days longer, the CIA's detainees also exhibited these symptoms. "At least five detainees experienced disturbing hallucinations during prolonged sleep deprivation and, in at least two of those cases, the CIA nonetheless continued the sleep deprivation," the executive summary states.

"It is unlikely that people were totally sleep deprived for that period," Schnyer said. "You would need to monitor people 24 hours and wake them continuously, especially if they aren't cooperating with staying awake. More likely, they just made it very hard on the people to sleep well but I suspect they were passing in and out of sleep even while standing."

The CIA may not have been able to keep someone awake for that long, and most sleep researchers wouldn't, but one intrepid researcher decided to put himself through this particular form of torture.

The longest that anyone has stayed awake in a controlled, experimental setting has been 11 days. In 1965, a 17-year-old high school student named Randy Garner stayed awake for 252 hours as a science fair experiment.

En route to the record, Garner's eyes stopped focusing on the second day, and he had trouble watching TV. He stopped being able to identify objects by touch, a condition known as astereognosis. By the third day Garner was moody, he had developed a lack of coordination, a "marked nausea."

By the fourth, his memory was lapsing, he was irritable, had difficulty focusing and was seeing fog around street lights, and imagined a street sign was a person. Then, according to a paper on Garner's research, Garner "imagined he was a great Negro football player and resented statements made about his ability and the Negro race."

You can see why the CIA publicly argue that such techniques are useless

Sleep deficits have been linked to the development of some chronic diseases and disorders, including diabetes, depression, obesity and cardiovascular disease. Schnyer told me that there were long-term consequences to sleep deprivation, as it "creates a cascade of metabolic reactions, many of them stress related and toxic to the brain."

The US military authorized sleep deprivation for up to 72 hours in a 2002 Department of Defense memo, a rule the CIA allowed itself to ignore. The agency itself admitted that torture wasn't productive at getting information, and it certainly didn't help that they also admit to torturing innocent people.

Arsala Khan suffered disturbing hallucinations after 56 hours of standing sleep deprivation, after which the CIA determined that he "does not appear to be the subject involved in... current plans or activities against US personnel or facilities," the executive summary stated.

Janat Gul also suffered "frightful" hallucinations following sleep deprivation. The chief of the detention facility then wrote, "[t]here simply is no 'smoking gun' that we can refer to that would justify our continued holding of [Janat Gul] at a site such as [DETENTION SITE BLACK]."